Gyroscopic control apparatus for air and other craft



May 4, 1948. P, WN 2,440,713

GYROSCOPIC CONTROL APPARATUS FOR AIR AND OTHER CRAFT Filed Sept. 18, 1944 3 Sheets-Sheet 1 Inventor H JRBRQWM A Ihrney;

y 4, 8 J. P. BROWN 2,440,713

GYROSCOPIC CONTROL APPARATUS FOR: AIR AND OTHER CRAFT Fil'ed Sept. 18, 1944 3 SheecS-Sheet 2 Inventor B i Wiillomep May 4, 1948. BRO N 2,440,713

GYROSCOPIC CONTROL APPARATUS FOR AIR AND OTHER CRAFT Filed Set. 18, 1944 3 Sheets-Sheet 3 W A ltorne trcl.

Patented May 4, 1948 GYRosooHc CONTROLAPPARATUS FOR'.

AIR AND OTHER oaAFr John Pollock Brown, Croydon, England Application September 18, 1944, Serial'No. 554,701

In Great Britain April 30, 1943 8 Claims. (cull- 144) This invention relates togyroscopic control apparatus applicable to air or othercrait. An example of the apparatus to which the invention may be applied is described in the specification of the present inventors United Statesof America Letters Patent No. 2,036,914, though it is to be understood that it may be used with other constructions of gyroscopic apparatus employed for like purposes.

In the construction described in the specification of the above mentioned patent the rotor of the gyroscope is mounted with a spherical cup bearing on a ball carried on the end of a spindle which is driven by suitable meansthe drive being transmitted by slipping fluid friction to the rotor so that the latter is free to change its angular position with respect to the driving spindle. The rotor with its driving spindle and the valves controlling servomotors are mounted on a cradle which is itself supported so as to be movable about two axes at right angles to each other on a base plate. The rotor controls the valves of servomotors which move the cradle about each of these axes which may be referred to as the axes of con On deflection of the base plate, that is to say if the craft in which the apparatus is mounted deviates from its set course, theseservomotors operate to bring the driving spindle again into alignment with the axis of the rotor and in so doing the valves of the servomotors are restored to their normal positions. At the same time and throughsuitable servomotor mechanism the navigating controls of the craft are actuated in such a sense as to keep the desired attitude of the craft, that is to say to maintain the craft on its course and in the case of an aircraft to also maintain its altitude. Inthis construction the control of the valves of the servomotors is effooted automatically by the rotor by providing the rotor with a projection which extends from its centre coincident with its axis and in a direction opposite to the driving spindle. This projecting arm engages two light forks which lie at right angles to each other and in a common plane which is normal to the axis of the driving spindle. Each of these forks is so mounted that it can be moved in the plane in which it lies by the arm projecting from the rotor if the axis of the driving spindle is caused to deviate from coincidence with the axis of the rotor. Such movement of a fork will actuate the valves controlling a servomotor which acting through suitablemechanism will swing the cradle through one of the axes about which it can be turned andthus restore alignment between the driving spindle and the axis of the rotor and therebyat the same time restore to their normal positions the valves which had been displaced by the deflection with. respect to the axis of the rotor. This deflection will have been due to a movement of the craft, either in azimuth or in altitude, from its correct or set attitude or course. The servomotors func. tion either directly or through relays to operate thenavigational controls necessary to bring the craft back to. its correct attitude. In the existing arrangement the construction produces action by the servomotors which is proportionate to the deflection of the rotor and effects a corresponding operational control of the craft. Owing, howeveryto the mass of the craft which must develop momentum when a disturbance occurs leading to a deviation from the set course, this control cannot adequately deal with or damp down an excessive disturbance such as the rapid yawing of a craft whether. aircraft or ship. The present invention provides means whereby this difiiculty can be effectively dealt with automatically.- 5

According to this inventionin directional Icontrol apparatus of the type indicated above there a is combined with a servomotor operating direction controlling mechanism, means which as and when deviation from a set course has occurred tend to restore to normal positionsthe displaced parts of the apparatus and through it check and bring the craft back on to its course, and means which by offering a resistance cause automatically a delay in the restoration of the apparatus for the purpose of dealing effectively with excessive; rate of yaw and like movement of the craft controlled by the apparatus. The resistance which thus delays the restoration to normal comprises a retarding device associated with the mechanism for restoring the valve by whichis controlled the operation of the servomotor which transmits the movements necessary to bring about the restoration of the craft with a minimum of oscillation about its set course. There is a yielding connection between the servomotor operating the navigating control apparatus and the mechanism whichineludes an intermediate lever and a floating lever associated with the retarding device by which a mechanism the valves of that servomotor are act- ,on each side of the pin but permit it to occupy a definitely neutral position between them while rod- P will cause'the enlargement P to slide out from one end on the sleeve P'fowing to the resistance ofiered to movement of the lever L by the retarding device NP. One-"spring P will then be carried as a whole with the rod owing to the loose collar P' butting up against the end face of the enlargement I", but the other spring P will be compressed between'the fixed; collar .E' on the rod and the endfaceof the sleeve P against which the loose collar P will then ab'ut. A force will thus beapplied to the lever L but its movement will be delayed'bythe retarding device M". Owing to this delayed action the servomotor N as a result of the craft yawing in the opposite direction, may have been caused to impart a counterclockwise movement of the lever before there can have taken place movement of the lever L corresponding to man a clockwise movement of the; lever; 0; If the servomotor N is caused to move-thelever 0" slowly, then a corresponding movement of the lever L will be efiected morereadily. g

The valves which control the'flow of pressure liquid through the pipes N to the servomotor N are situated in a casing N and actuated by movement of a floating lever Q in the following manner. The lever L isfprovided with a second arm L which is connectedthrough' a link L to one end of the lever Q. At its other end this lever engages through a pin Q a notch R formed in the periphery of a disc R fixed on the spindle D of the rotatable casing D. Acoiled spring Q is attached at its ends to the pin Q b'eingpassed round a grooved heel R carried by the disc R and thus mounted on the spindle D. If the casing D with its spindle and the disc R is turned the lever Q will be swungin one direction or the other against the action of the spring: Q At a point Q intermediate in the length of the floating lever Q it is connected for instance through a link N or some equivalent linkage structure with a lever N which as it is moved about its pivot N will actuate the valve or valvesjin the casing N which control the flow or pressure liquid to the servomotor N. This arrangement may conveniently be referred to as the valye-oper ating linkage. q

The improved apparatus operates in the following manner when installed, say, in a-seacraft. If the craft yaws, for example, to port, the whole apparatus will swing to port with the craft, but as the rotor A will not partakein this movement the driving spindle B will then be out (ii -alignment with the rotor arm A. The latter acting through the fork F will move the valve in the casing H and cause the servomotor J to move the rack K and thereby turn the rotor casing D inazimuth so as to restore alignment between; the driving spindle and rotor arm. If this servomotor was connected to the mechanism for, actuating the rudder, as in the known app-aratusthe servomotor as it turns the casing D would apply helm to the rudder in the sense necessary to bring the craft back on to its course This action of the rudder would cause aswinging movement of the whole apparatus to starboard with the craft then causing displacementof the valve and consequent rudder action and as realignment between the driving spindle and the rotor arm is reached the valve of the servomotor J in the casing, H will be restored to its normal position as the rudder comes amidships. A

In the present apparatusghowever, the yawing of the craft and the accompanying movement of the apparatus brings about movement of the valve of the second servomotor N and thus through this servo indirectly operates the rudder by the servomotor acting on the lever 0. Owing to the interconnection efiected by the floating lever Q between firstly the casing D acting'through its spindle D and the disc R on one end of the floating lever Q, secondly the lever L L" acting on the other end of the floating lever Q and itself controlled by the retarding device M and actuated through the yielding connection and'thirdly the linkage N N operating the valves of-the servomotor N, the restoration of the alignment between the driving spindlle B and the rotor arm A will take place while retaining some degreeof helm proportionate to the angle of yaw. The response of the craft must lag behind the actual movement of the rudder and without this means of delaying the restoration of the servomotor valves there will tend to be a hunting action with helm applied first on one hand and then on the other. Hence the more that the restoration of the valves of the servomotor N is delayed the more will this servomotor respond with a temporary action on the rudder and if this action is correlated to the rate of yaw then the application of helm will be adjusted to accord with this.

' When therate of yaw has been checked it will be reflected in the resilience in the linkage mechanism which performs the ordinary positional control of the valves of the servomotor N. For example, if the craft yaws rapidly enough to cause the apparatus to apply fullhelm of, say 30, even if the yaw be checked when only 15 has been reached, the restoration of the valves of'the servomotor N, owing to fading out of the rate of movement imparted through the resilient connection, will have a reaction on the rudder, through the valves and servomotor, by bringing these back to their normal positional relations. v

If in the follow up movement of the casing D the disc R is turned so far that the pin Q on the end of the floating lever Q comes out of the notch R, this pin will lie on the periphery of the disc and the end of the lever Q will be held against further movement. The pin Q will, however, drop back into the notch R as the disc turns back into its normal position and it will carry with it the end of the floating lever Q. As this lever turns about its other end which is connected to the lever armL the valves in the casing N will be set so as to cause the servomotor N to return the directional control mechanism to its normal position for maintenance of the true course.

The degree of resistance offered by the retarding device M may be adjustable as for instance by providing known means for altering the angle of the blades or vanes.

The details of construction may be varied in accordance with requirements.

What I claim as my invention and desirelto secure by Letters Patents is:

1. Gyroscopic apparatus for use in the control of air and other craft comprising in combination a rotor with means for driving it, a base rigidly mounted in the craft, a support for the rotor and its driving means this support being movable about at least one control axis with respect to the base, a servomotor operative to move this sup port about the saidcontrol axis, a valvecontrolling said servomotor and arranged for operathe base, a second servomotor operative on mechanism through which the course of the craft assen -e 7 is;dietermimad.v a? valvecontrolling; this, second senvcmoton means whioh-gwhemthe: craft deviates fro eitsgsetcourse are:operativetthm hithe'said. rotonto aetuatetha'valvecontrollinathesaidfirst mentioned .servomotor and. cause, it. to turni the saidLnotor support about azcontroltaxis and;imso doing; actuate the valve controllingythe. saidsecnd; senvomoton whereby the mechanism: which determ-inesithe; courselofs.thefcraftfwill .be caused to.-restore the: crafttoits; correct course;., and

meanswhich' offer-- a resistancmtoand cause-all.- tomatically al-delay inithelrestoration to-normal positions oithe elements: that aredisplaced. by suchldeyiationu v i i Gxroscopic',apparatus fon use :in. the control oi, air andother craitlcomprising in combination arotor with: means ion driving it, a? base; rigidly mounted. in; the craft; a, support? for. the. rotorand its; driving; means? this. support: beingg mow able about; atleast one I control axis: with respect toltheba'se, atservomotor operative. to movesthis support-(about the said. control. axis a-pvalvecontrolling saidiservomotor and: arranged fonoperae tion; by movementof the-rotor support nelative tori r11 6, base. at secondv servomotor; operative: on mechanismthroughwhich theicoursegef the craft is determined, a valve controlling. this. second senvomotor; means: which; when:v the. craft deviates :from itsset course are operative through the. said-inter tolactuateitheevalve .contnollingthe said first. mentioned senvomoton and, cause it to turn. the: said roton supportr about a: control axis andin-lso doingyactuam thevalvecontrolling the said second servomotor whereby the mechainism. which: determines the course, of; the craft will be caused to restore. the craft; to its 0101', rectcourse, and ai retarding, devicevwhich is connected to the. mechanism; which actuates the valve. of, the said. second. senvscmotor. and. causes a resistance to and automatically delays the: restoration to normal positions the elements that are, displaced by such; deviation.

3. Gyroscopic; apparatus for use in thecontrol ofij airand, other craft-comprising: incombination arotor. with means; for. driving it," a base: rigidly mountedin-the craft, asupportjor-the rotor and its. driving; means this supper-h being movable about. at least. one control: axis with respect to the: base, a. servomotor. operative to move this support. about the.- said control axis; a: second servomotor operative on. mechanism.- through which the: course of the craft; is: determined; a veins controlling. this; second, servomotor, a floating. levermeans b3? which this, letter: is moved when. as a resultlof the; craft deviating from: its set courserthe-said-supportis moved: about a control, axis, a connection betweemthissfloatinglever and thevalve of the saidsecond: senvomotor,-. a yielding connection between this; floating lever and, the mechanism. operated-by theisaid. second servomotor which. controls; the; course? 01; the craft, movement of; the.- saidiloatingy-leaen byvt-he said means resulting; in: nestonation. tot normal positionsthe elements of; thevapparatus' displaced by; such. deviation in: the:; apparatus as; the devie ation. of the, craft is; checked anditbrought back; on to its correct. course, and meanswhich ofiier; a. resistance. to and; causev automaticallya delay. in. this; restoration.

. 4.. Gyroscopicapparatus foruse in-lthe control 0t. air. and. other craft comprising in combination a. rotor. with means for. driving: it, a baserigidly mounted, in the craft, a. support. for. the rotor and.: its? driving. means: thisl support being mavahles aboutatl least-one; contmL axiswith. respect tetnelbase a lser iomoton Opfilati-Sle: to move: this support aboi-nathe: said: controL axis at second servomoiton operative; on... mechanism; through which: the. course: of the craft, is: determined, a valvezccntrolling'thistsecond servomoton a.--floatmg. lever; meanse by which? this lever. is, moved when. asca result oigthe. craftdeviating; fromlits set: course-the.saidlsupportiisrmoved'about ga cone trollaids a. connectionibetweenithis floating ,lever ancclthe. valveeot. theesaidl second. servomotoraan intermediate lever. pivoted. on-ther said! base. and connected to: thesaid-fioating lever, .meansrcperae tive on; this intermediate levenandofhringarea sist'ance.-: to; its: movement-,-. and a yielding; con: nection=between-l this mtermediatedever, and the mechanism, operated-by. the said: second servo.- moton which. controls; the course. of: the.- craft, movementaof; thesaidz floating. lever by: the. said intemnediateleven resultinggimrestoraticn.to nor.- mahpesitionsethe.elementslof therapparatus-displaced; by, such. deviationini the. apparatus lassth'e deviation of the craft-is checkediandzitisbrought beckon to. its coursegbut-such; restoration being delayed a the; said; resistance ofieneda to; the movement-loft theintermediateleven U 5. Gyroscopic ar'gparatusr for use: im the: control otair. and. othen craftt-comprising in: combination a rotor. with; means for.- driving it, abase rigidiy mounted; in the craft a. support fonthe-rotorrand its driving means. this support being,- carried'eby averticallspindle constituting a contnoleaxis for thegsupport and-.thmlatten with.- the; spindle. being rotatable. on the. said, base, a? valvecontrolling said, servomotor. and, arranged; for. operationE by movement of: the; roton support. relative tothe base, a .senvomotor operative. to. rotate: thesaid spindle, and. support a second; senvomotorr' op.- erative'ron mechanism. through Which-thecom'se of the; craft isdetermined, a-valve controlling this. second. servomotor,, means. which when the craft deviates: from. its. set course are operative throughthe-said rotor. to actuateithe-valve con.- trolling, the. said firstmentioned senvomoton and cause. it to rotatev the i said: spindle; and: support carriedthereby means whereby; this. rotatiomoi the spindle and supportlactuates,theesaid-valve controlling the said second servomoton Whichtby amotor with-.meanslfon driving it,.a base. rigidly mounted-.inthe. craft, alsupportfon the;.rotor-: and its-driving means.v thisi support being carried. by; a vertical; spindle rotatable on. the; said! baseand eonstituting a} control. axis for the support. a servomotor operative? torrotatel the. said. spindle andisupport, avalvecontmlling said-senvomotor and; arrangedifor. operation-by, movement, of! the rotor.supportlrelatmetdthe baseialseconds rvo- 11101501? operative. on: mechanism: through, which thel course, of; the crafti's; determined; a. valve controlling... this; second; servomoton. a. floating lever, ,meansmhich. whenithe craitrdeviatesifrom its set; course are operative, through, the said rotor to actuate; the. valve controlling; the: said first mentioned servomotor. andoause. itvto 11o..- tatev the said; spindle and. the su gpflrt. carried thezzebxt a. connectionl between; the? floating; lever and: the-said. spindle such} that whom as a. result of the craft deviating from its set course the said support with its spindle is rotated movement will be imparted to the floating lever, a connection between this floating lever and the valve of the said second servomotor, a yielding connection between this floating lever and the mechanism operated by the said second servomotor which controls the course of the craft, movement of the said floating lever by the said means resulting in restoration to normal positions the elements of the apparatus displaced by such deviation in the apparatus as the deviation of the craft is checked and it is brought back on to its correct course by the action of the apparatus, and means which offer a resistance to and cause automatically a delay in this restoration.

7. Gyroscopic apparatus for use in'the control of air and other craft comprising in combination a rotor with means for driving it, a base rigidly mounted in the craft, a support for the rotor and .its driving means this support being movable about at least one control axis with respect to the base, a servomotor operative to move this support about the said control axis, a valve controlling said servomotor and arranged for operation by movement of the rotor support relative to the base, a second servomotor, a lever from which extend connections to operate the rudder of the craft, means by which this lever is moved by the said second servomotor and the course of the craft thereby determined, a valve controlling this second servomotor, means which when the craft deviates from its set course are operative through the said rotor to actuate the valve controlling the said first mentioned servomotor and cause it to turn the said rotor support about a control axis and in so doing actuate the valve controlling the said second servomotor and cause it to move the rudder operating lever and thereby restore the craft to its correct course, and means which offer a resistance to and cause a delay in the resultant restoration to normal positions the elements of the apparatus displaced by such deviation in the apparatus.

8. Gyroscopic apparatus for use in the control of air and other craft comprising in combination a rotor with means for driving it, a base rigidly mounted in the craft, a support for the rotor and its driving means this support being carried by a vertical spindle rotatable on the said base and constituting a control axis for the support, a servomotor operative to rotate the said spindle and support, a valve controlling said servomotor and arranged for operation by movement of the rotor support relative to the base, a second servomotor, a lever from which extend connections to operate the rudder of the craft, means by which this lever is moved by the said second servomotor and the course of the craft thereby determined, a valve controlling this second servomotor, a floating lever, means which when the craft deviates from its set course are operative through the said rotor to actuate the valve controlling the said first mentioned servomotor and cause it to 1'0- tate the said spindle and the support carried thereby, a connection between the said spindle of the support and one end of the said floating lever such that when the support with its spindle is turned movement will be imparted to the floating lever, a connection between this floating lever and the valve of the said second servomotor, an intermediate lever pivoted on the said base and connected to that end of the floating lever opposite to that which is connected to the said spindle, an inertia device operative on this intermediate lever and offering a resistance to its movement, and a yielding connection between this intermediate lever and the said rudder operating lever.

JOHN POLLOCK BROWN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

